CVE-2026-118373mediumCWE-319

CVE-2026-118373: medium-severity vulnerability in OpenBSD LibreSSL

LibreSSL ocspcheck through 4.4.0 Cleartext Transmission of OCSP Requests via url2host()

Published

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13Vexday Risk Score

No sign of exploitation. No public exploitation artifact known so far.

ssvc Trackcvss 6.3epss 0.1%
LibreSSL ocspcheck through 4.4.0 contains a cleartext transmission vulnerability because url2host() discards the OCSP URL scheme and http_alloc() only selects TLS for port 443. On-path network attackers can read OCSP requests sent to https responder URLs on non-443 ports, exposing certificate serial numbers, issuer hashes, and nonces.
CVSS:4.0/AV:N/AC:H/AT:P/PR:N/UI:N/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N
Affected products
OpenBSD · LibreSSL
Related CVEs — OpenBSD LibreSSL

In the same product, most dangerous first.

CVE-2026-118374HIGHLibreSSL ocspcheck through 4.4.0 Memory Exhaustion via Unbounded OCSP HTTP ResponseEPSS 0.2%CVE-2026-118372MEDIUMLibreSSL ocspcheck through 4.4.0 CRLF Injection via AIA OCSP URL PathEPSS 0.1%CVE-2026-118371MEDIUMLibreSSL through 4.4.0 CRLF Injection via OCSP_sendreq_new() Request LineEPSS 0.1%